3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Noonan <steven@xxxxxxxxxxxxxx> commit a9f180345f5378ac87d80ed0bea55ba421d83859 upstream. I started noticing problems with KVM guest destruction on Linux 3.12+, where guest memory wasn't being cleaned up. I bisected it down to the commit introducing the new 'asm goto'-based atomics, and found this quirk was later applied to those. Unfortunately, even with GCC 4.8.2 (which ostensibly fixed the known 'asm goto' bug) I am still getting some kind of miscompilation. If I enable the asm_volatile_goto quirk for my compiler, KVM guests are destroyed correctly and the memory is cleaned up. So make the quirk unconditional for now, until bug is found and fixed. Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Steven Noonan <steven@xxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Jakub Jelinek <jakub@xxxxxxxxxx> Cc: Richard Henderson <rth@xxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1392274867-15236-1-git-send-email-steven@xxxxxxxxxxxxxx Link: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/compiler-gcc4.h | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) --- a/include/linux/compiler-gcc4.h +++ b/include/linux/compiler-gcc4.h @@ -75,11 +75,7 @@ * * (asm goto is automatically volatile - the naming reflects this.) */ -#if GCC_VERSION <= 40801 -# define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) -#else -# define asm_volatile_goto(x...) do { asm goto(x); } while (0) -#endif +#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) #ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP #if GCC_VERSION >= 40400 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html